I too was symptom free until about 6 months prior to having the surgery. On the news one day, there was a piece about a dust cloud from the Sahara Desert coming across Europe, picking up pollution as it worked its way to Southern England, and indeed as I did my usual 6 minute walk to my train station for my commute to work, with a dusting of sand visible on parked cars, it was as if someone had flicked a switch, and I could only walk 300 yards or so before feeling breathless. I had to stop for a few minutes and then could carry on normally, but again only for 300 yards each time. Needless to say I thought it was respiratory, because of this pollution, and it was 5 months or so before I got to have an ultrasound test that revealed it was severe aortic stenosis. I ended up having a "cardiac event" at home one Sunday afterwards - to me it felt like I thought a heart attack would be like, though apparently no damage was done to my heart. So I called an ambulance, and after more tests, a week later had the valve op.
In my case, the surgery damaged my heart's electrics, which is I think about a 6% risk or less, given that the heart's electrics are around the valve and not exactly colour coded. So I ended up with a pacemaker a week later too. That has been no big deal either, but in total I spent 25 days in hospital.
I know this is going to sound weird, but I mostly have fond memories of my time in hospital! When they did the angiogram, inserting the probe into an artery in my groin as I lay on a trolley beside the biggest plasma TV screen I had ever seen, there was no pain and I was fascinated to watch the flashes on this TV and see the robotic arm move around me as they presumably took x-rays at different angles and progressed into my heart. At the end of the procedure I said "I enjoyed that - same time next week?" !
Yes, there is discomfort/mild pain when you try to move for the first couple of weeks after they have rummaged in your chest, and I was amazed at how much I urinated out, annoyingly after they had removed the catheter thing. But the medication for pain management is really good, and it is such a routine thing that the whole process is very well managed, resulting in only low levels of pain.
My tip would be to prepare for the recovery period once you get home. I normally sleep on my side, but you can't do that whilst the chest knits itself back together again, and I found an electric recliner wonderful for getting into just the right position to sleep on my back but reclined, moving the chair an inch or two for optimum positioning, and then getting out of the chair was easy by returning to the upright position. You need to maintain excellent standards of hygiene - eg don't share your towels with anyone else, and only use 2 or 3 times before washing them. Don't let visitors touch the wound area, or frankly have any physical contact with you - the last thing you want is either an infection, or a picking up a cold and coughing whilst your chest is repairing itself.
That was over four years ago now, and the only things to deal with are annual checkups for the valve, separate annual checkups for the pacemaker, and weekly testing of my blood INR using a hand held finger prick meter at home to make sure I am taking the right amount of Warfarin. In fact it is time for me to do this week's test now